Malicious PDF — malware analysis report

Static analysis result for SHA-256 a0ac204d637544fc…

MALICIOUS

PDF

79.7 KB Created: 2021-09-17 17:38:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-20
MD5: f15b5e2c4bd306bf0a4e0c1c7a52f737 SHA-1: 9df34843da83b1e125d1e81760411576973fe643 SHA-256: a0ac204d637544fc4aab9104de09c0e63873900400e834f2f8b326d4de7cbae6
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous embedded URLs, many of which point to compromised CMS upload storage or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution through these links. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, further supporting its role as a container for malicious links rather than user-facing content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://wastran.ru/uplcv?utm_term=the+good+witch%27s+gift+online+free PDF link annotation
    • http://ohxto.com/uploaded_files/userfiles/files/daxewomibano.pdfIn PDF document text
    • http://orderleesushi.com/uploads/files/makikibozexatukexof.pdfIn PDF document text
    • https://pharma-tools.eu/galeria/file/duvuxabewaviliduxusugo.pdfIn PDF document text
    • https://samavetpharm.com/userfiles/files/pakedagofixo.pdfIn PDF document text
    • http://auto-rad.pl/userfiles/file/51244920836.pdfIn PDF document text
    • http://namjapizza.com/app/webroot/files/xenuvijexidakomijepulew.pdfIn PDF document text
    • http://udokutscher.de/gfx/userfiles/files/xiganekos.pdfIn PDF document text
    • http://www.smpnuenen.nl/images/files/zigesozawuguxomikelaw.pdfIn PDF document text
    • https://tumujerrusa.com/userfiles/bogilanakoje.pdfIn PDF document text
    • http://bularz-auto.pl/images/userfiles/file/navebelidijujaravobodutu.pdfIn PDF document text
    • https://batdongsandothanh.vn/luutru/files/dafuson.pdfIn PDF document text
    • https://www.hkha.com.hk/ckfinder/userfiles/files/74492038798.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612fe6b235b3d---nolusobemukuketuripifo.pdfIn PDF document text
    • http://alnadaoil.com/userfiles/file/wijufosadak.pdfIn PDF document text
    • https://shrmivirtual.org/wp-content/plugins/super-forms/uploads/php/files/fcceb452373813dbe7b1787b88cab889/58067953522.pdfIn PDF document text
    • http://daotaonhaccong.com/uploads/userfiles/file/50061818697.pdfIn PDF document text
    • https://rcvizovice.cz/ckfinder/userfiles/files/xoxob.pdfIn PDF document text
    • http://paymentsbusiness.ca/wp-content/plugins/formcraft/file-upload/server/content/files/161408afff00af---nogadalumusavoxijubi.pdfIn PDF document text
    • http://atya.eu/files/file/wajonunawizofem.pdfIn PDF document text
    • https://synersys.fr/contenu/file/74692903941.pdfIn PDF document text
    • https://bitree.ru/ckfinder/userfiles/files/89070131703.pdfIn PDF document text
    • https://mvmdigital.gr/files/files/paxujar.pdfIn PDF document text
    • http://nhanvietgroup.com/demo/xay-dung-tnx/upload/files/25349362756.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d0b7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD0B7 18312 bytes
SHA-256: ed8c7200f79527c8b2d69cbf3767ee58ee5fa341c8a85a08ed283bf00e78b342
font_01_sfnt_off0001006f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1006F 10676 bytes
SHA-256: eda733d793da22b52b311551a20489b50aeb6bda6df5cf28d99057de6b786fca
font_02_sfnt_off000118be.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x118BE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1